JPS6232467B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic copying apparatus, and more particularly to an apparatus for recording or printing figures, numbers, symbols, etc. on recording paper based on sequentially transmitted data.

Conventional electrical recording and processing devices typically (1) create a charged area on a selected member of the recording medium, (2) develop the charged area on the recording medium, and then (3) create a developed area on the recording medium. The recorded information was fixed by pressure and/or heat so that it remained on the medium permanently. The present invention relates to the above-mentioned part (1), that is, an improved device for forming a charged area on a recording medium.

Various techniques and devices have been proposed for forming electrostatic charges of sequentially transmitted electrical signals on recording paper to obtain a hard copy. U.S. Patent by Murray et al.
No. 3,757,352 is one such example, in which a conductive paper with a dielectric layer is fed from a roll and receives an image by electrostatic charges formed by three pulsed line scanning needles in direct and sequential contact with its surface. . This needle is removably fixed to an endless belt that moves at a constant speed in a direction perpendicular to the direction of paper movement. Other examples include U.S. Pat. No. 3,050,580 to Schwarz or U.S. Pat. An electrostatic charge image is formed in the latter having a plurality of electrodes mounted in series on an endless belt moving in a direction perpendicular to the direction of paper travel. However, these prior art techniques are relatively complex and expensive, and suffer from various drawbacks due to ambient conditions, tolerances, etc., not all of which will be listed here, which may be of varying degrees of severity. Another drawback is the synchronization problems required of copiers when high quality copies are required.

Furthermore, conventional devices that use an endless belt require a mounting member to attach or fix the needles on the belt, which complicates the configuration of the needle assembly and increases the weight. In terms of accuracy and durability, it was unsuitable for applications in which high-speed, high-precision recording is performed by running. Particularly when a conductive endless belt is used and voltage is supplied to the needles via the belt, the needles are attached to the belt by, for example, metal blocks, which places a large burden on the belt.

On the other hand, when using a non-conductive endless belt, in addition to the needle attachment member, there is also a voltage supply bar installed parallel to the belt to supply voltage to the needles, and a needle to transfer voltage from this bar to the needles. This requires a contact provided integrally with the contactor, making the configuration complicated. Moreover, since conventional needles usually use wires, they have the disadvantage that the needles tend to vibrate in a direction perpendicular to the running direction while the endless belt rotates.To prevent this, conventional devices A vibration suppressing means such as a guide rail was required to suppress the vibration of the needle. This results in increased complexity and cost of the device.

Furthermore, in the past, the position of the needle was directly detected by optical or magnetic detection means, which had the disadvantage that the position of the detection means was limited to the position at which the needle started scanning. Ta.

Accordingly, one of the objects of the present invention is to provide an improved electronic reproduction apparatus that eliminates the disadvantages of the prior art.

Another object of the present invention is to provide an improved electronic reproduction apparatus that is relatively simple and inexpensive to construct.

Still another object of the present invention is to provide an improved electronic copying apparatus that has an endless belt and a segment platen having integrally formed needles (recording needles) and forms an electrostatic charge image on the surface of a recording medium disposed therebetween. It is to provide.

The above-mentioned and other objects, advantages, and operations of the present invention will be more fully understood from the following description of a preferred embodiment thereof and the accompanying drawings. However, these examples are not intended to limit the technical scope of the present invention in any way, but are merely provided to enable those skilled in the art to fully understand the principles of the present invention and how to put it into practice. It is clear that various modifications and variations of the optimum are possible.

Briefly, the reproduction apparatus of the present invention is such that a sheet of paper is fed onto a segment platen and a charge image is formed by needles that directly and sequentially contact the dielectric surface of the sheet. This needle is integrally formed with an endless belt that moves laterally across the surface. A voltage pulse corresponding to the input information is applied to the segment platen to form an electrostatic charge. This latent image charged surface is then subjected to a sequential image toning and fusing cycle to form a hard copy.

Since "mechanical scanning" is performed by moving this needle, an image can be formed anywhere on the line.
To form a high-quality copy and eliminate the drawbacks of the prior art. Resolution can be increased by controlling the pulse period and surface velocity. Furthermore, since the needles are integral with the endless belt, they are relatively simple and inexpensive to manufacture. Also, since two or more hands are recording at the same time, the recording speed increases. In the present invention, one of the pulleys is steered using a simple mechanical sled so that the positional relationship between the belt and the needle can be easily maintained without having to center or height the drive pulley or using complicated positioning means. Maintain or hold the belt in place.

One embodiment of an electronic reproduction apparatus according to the present invention is shown in FIGS. 1-3 and includes an endless electrically conductive belt 10 rotating about rotating pulleys 12 and 14. The belt 10 is preferably "303" type fully tempered stainless steel approximately 0.025 mm thick and approximately 12.7 mm wide. Although not shown, the pulley 12 is rotated in the direction of arrow 16 by well-known means such as a drive shaft. Marking needles 18 in the form of protruding pins cut out of a part of the belt 10 and provided at selected intervals are used to mark a recording medium, that is, a piece of paper 20, during a period of rotation between the pulleys 12 and 14. Touch and pass. The contact end of each needle 18 is plated or bonded with a hard material, such as chrome, or otherwise coated with a hard material. belt 10
has a plurality of first timing marks or tracks 22, one for each needle. Each timing mark 22 is provided near the tip of each needle 18 to indicate the exact position of the needle 18. Since the recording signal is controlled according to the timing mark 22, even when a plurality of needles 18 are used, it is not necessary to set the intervals between the needles at equal intervals with high precision. In the embodiment, each timing mark 22 is provided near the tip of each needle 18, but it may be provided on the belt at a constant distance from each needle 18. Therefore, the set positions of the timing mark detection means 40 and 42, which will be described later, are not limited to the scanning start position of the needle 18. Each timing mark 22 is also formed by selectively cutting away a portion of belt 10. In addition to timing mark 22, a second timing mark 24 is provided on belt 10. As can be seen, several timing marks 24 are provided for each timing mark 22, so that the timing between belt 10 and paper 20 can be precisely controlled. Alternatively, timing marks 24 may be provided in the conventional means described during drive of pulley 12 to control or reduce slippage between belt 10 and pulley 12.

At the same time, the paper 20 is driven by other known means (not shown). The moving direction is substantially perpendicular to the moving direction of the needle 18, that is, the direction indicated by the arrow 26, and contact lines that are close to each other are formed on the recording paper 20. This line pattern, that is, the resolution is of course needle 1
8 and the recording paper 20 can be controlled by the relative movement speed between the recording paper 20 and the recording paper 20. As a typical example, a pulley with a circumference of about 10 cm rotating at 3600 RPM is driven to move the belt 10 at a speed of about 6.1 m/s, and move the recording paper 20 at a speed of 30 mm/s.
If you move at a speed of , you can get a resolution of about 80 lines per cm. This resolution provides a good quality copy. The recording paper 20 is preferably somewhat electrically conductive and is preferably provided with a layer 28 of a suitable insulator (dielectric). The recording paper with these characteristics is electronic copying paper A2504 manufactured by Crown Zerabak. The back surface 30 of the recording paper 20 is somewhat conductive,
It is in contact with a conventional voltage-controlled back electrode group 32 . Each back electrode 32 receives voltage pulses via conductor 34 from a voltage source 36 under the control of timing stage 38 . These voltage pulses are applied at controlled timing between the needle 18 and the back electrode 32 to form an electrostatic charge image on the insulating layer 28. Additionally, the timing stage 38 receives a plurality of belt timing signals from the light collection means 40 to control the voltage source 36 and the belt recording paper drive means (not shown). Since this light passes through the apertures forming timing marks 22 and 24, these timing signals are directly proportional to the amount of light received by means 40. This light is applied from a light source 42, and the light emitted from the light source 42 is configured to either pass through the aperture or be blocked by the belt. Although a lamp and a phototransistor are shown as the light source 42 and the condensing means 40, it is also possible to emit light using other means such as an LED (light emitting diode) and condense the light with a CCD (charge coupled device).

The charge pattern electrostatically formed on the insulating layer 28 of the recording paper 20 according to the present invention is converted into a visible image by the addition of toner and then fixed by conventional techniques described in U.S. Pat. No. 3,757,352. This specification describes a technique for selectively adhering to the layer a pre-charged toner, i.e. tribostatically charged and colored plastic particles, with a polarity opposite to that on the surface of the dielectric layer. . The charge on the toner is created by intimately mixing it with another substance called a carrier, for example spherical iron scraps. If you choose appropriately,
This carrier is not attracted to the electrostatic charge image during the period in which the toner is deposited on the charged surface of the recording paper.
Fixation of the visible image corresponding to the charge pattern is accomplished by heating the toner to the interstices of the plastic component, which solidifies as it cools, allowing the toner to adhere to the dielectric surface. Since converting a charge pattern into a visible image is a well-known technique and does not form an essential part of the present invention, we believe that a detailed explanation of this is unnecessary.

Next, FIG. 4 will be explained. The figure shows an endless belt 1 running on rotating pulleys 12 and 14.
6 shows a belt tracking mechanism controlling the zero position. In this figure, the timing marks on the belt 10 are omitted for the sake of simplicity. This belt tracking mechanism allows the endless belt 10 to
14 as a reference to ensure that the device can remain in a predetermined position reliably and accurately without shifting in the lateral and axial directions. In this embodiment, the movable pulley 14, which is a non-driven pulley, is mounted on a bearing (not shown) of the ear shaft 50. A lever 52 is removably attached to the ear shaft 50, and two sliding portions 54A-54B are attached to the other end. The endless belt 10 slides between these two sliding portions while being in contact with each other. Of course, the runners 54A-54B have convex belt contact surfaces.

The ear shaft 50 has a pivot post 56 and is mounted for laterally rotation within a girdle 58. In the preferred embodiment, the post 56, i.e. the shaft, is connected to the pulley 1.
It coincides with the center of 4. Girdle 58 is provided with a slot 60 into which shaft 56 is inserted so that it can be removed and applied with appropriate belt pressure by spring 62. Girdle 58 also includes means, such as holes 64, for attaching the girdle to the chassis of the reproduction machine by conventional techniques such as screws, not shown.

Basically, a flat belt runs on flat cylindrical pulleys and moves in that direction when the pulley axes converge. This phenomenon is utilized by controlling the position of the ear shaft attached to the pulley with reference to the belt. This belt 10 has a sliding portion 54A-
Since the belt travels between the belts 54B and 54B, if there is a lateral movement, the belt moves the lever 52, which rotates the ear shaft 50 in an appropriate direction and returns the belt to its original position.

As described above, according to the present invention, since the recording needle is formed by cutting and raising a part of the endless belt made of an elastic metal plate, the recording speed is improved compared to the conventional device in which the needle is attached to the belt by a needle attachment member. The needle is extremely robust and has a long life. Since no needle attachment member is required, the burden on the endless belt is reduced and the life of the endless belt itself is extended. Furthermore, since the recording stylus according to the present invention, which is formed by cutting and raising a part of an elastic metal plate, is less likely to vibrate, there is no need for means for preventing vibration of the recording stylus. Therefore, the number of parts is reduced and durability is improved, resulting in lower manufacturing and maintenance costs.

Furthermore, since a timing mark can be provided on the belt by forming an opening in a part of the endless belt, the timing mark 22 for detecting the position of the recording needle can be placed on the belt at a certain distance from the recording needle. By forming the detection means on the belt, various remarkable effects can be achieved, such as the setting position of the detection means is not limited to the scanning start position of the recording needle, but it becomes possible to select any position around the belt.

Although the present invention has been described above with reference to a preferred embodiment, the present invention is not limited to this.
It will be obvious to those skilled in the art that various modifications and changes can be made without departing from the spirit of the invention.

[Brief explanation of the drawing]

1 is a diaphragm of a main part of an electronic copying apparatus according to the present invention, FIG. 2 is a side view taken along line 2-2 in FIG. 1, and FIG. 3 is a partially enlarged view of the conductive belt in FIG. 1; FIG. 4 is a perspective view showing the principle of the belt following mechanism of the electronic copying apparatus according to the present invention. In the figure, 10 is an endless belt, 12 and 14 are pulleys, 18 is a recording needle, 20 is a recording medium, 22 is an opening, 32 is a back electrode, and 40 and 42 are detection means.

Claims (1)

[Claims] 1. A conductive endless belt having at least one recording needle and rotating between two pulleys is held at a predetermined potential, and a back electrode provided opposite to the endless belt is Apply the recording signal,
In an electronic copying apparatus that records an electrostatic charge image on an insulating recording medium that moves between the endless belt and the back electrode in a direction substantially perpendicular to the running direction of the endless belt, the endless belt is an elastic metal plate. An electronic copying apparatus characterized in that the recording needle is formed by cutting and raising a part of the elastic metal plate. 2. A conductive endless belt having at least one recording needle and rotating between two pulleys is held at a predetermined potential, and a recording signal is applied to a back electrode provided opposite to the endless belt,
In an electronic copying apparatus that records an electrostatic charge image on an insulating recording medium that moves between the endless belt and the back electrode in a direction substantially perpendicular to the running direction of the endless belt, the endless belt is an elastic metal plate. The recording needles are formed by cutting and raising a part of the elastic metal plate, and openings are provided on the endless belt at a constant distance from each of the recording needles. An electronic copying apparatus characterized in that a detecting means for the opening is provided near the endless belt, and the timing of the recording signal is controlled by the output of the detecting means.